RT Journal Article
SR Electronic
T1 Engineered ACE2 receptor traps potently neutralize SARS-CoV-2
JF bioRxiv
FD Cold Spring Harbor Laboratory
SP 2020.07.31.231746
DO 10.1101/2020.07.31.231746
A1 Anum Glasgow
A1 Jeff Glasgow
A1 Daniel Limonta
A1 Paige Solomon
A1 Irene Lui
A1 Yang Zhang
A1 Matthew A. Nix
A1 Nicholas J. Rettko
A1 Shion A. Lim
A1 Shoshana Zha
A1 Rachel Yamin
A1 Kevin Kao
A1 Oren S. Rosenberg
A1 Jeffrey V. Ravetch
A1 Arun P. Wiita
A1 Kevin K. Leung
A1 Xin X. Zhou
A1 Tom C. Hobman
A1 Tanja Kortemme
A1 James A. Wells
YR 2020
UL http://biorxiv.org/content/early/2020/08/04/2020.07.31.231746.abstract
AB An essential mechanism for SARS-CoV-1 and -2 infection begins with the viral spike protein binding to the human receptor protein angiotensin-converting enzyme II (ACE2). Here we describe a stepwise engineering approach to generate a set of affinity optimized, enzymatically inactivated ACE2 variants that potently block SARS-CoV-2 infection of cells. These optimized receptor traps tightly bind the receptor binding domain (RBD) of the viral spike protein and prevent entry into host cells. We first computationally designed the ACE2-RBD interface using a two-stage flexible protein backbone design process that improved affinity for the RBD by up to 12-fold. These designed receptor variants were affinity matured an additional 14-fold by random mutagenesis and selection using yeast surface display. The highest affinity variant contained seven amino acid changes and bound to the RBD 170-fold more tightly than wild-type ACE2. With the addition of the natural ACE2 collectrin domain and fusion to a human Fc domain for increased stabilization and avidity, the most optimal ACE2 receptor traps neutralized SARS-CoV-2 pseudotyped lentivirus and authentic SARS-CoV-2 virus with half-maximal inhibitory concentrations (IC50) in the 10-100 ng/ml range. Engineered ACE2 receptor traps offer a promising route to fighting infections by SARS-CoV-2 and other ACE2-utilizing coronaviruses, with the key advantage that viral resistance would also likely impair viral entry. Moreover, such traps can be pre-designed for viruses with known entry receptors for faster therapeutic response without the need for neutralizing antibodies isolated or generated from convalescent patients.Competing Interest StatementA.G., J.G., I.L., X.X.Z., T.K., and J.A.W. have filed a provisional patent related to this work